The present invention relates to certain acetylene, or ethynyl, terminated aromatic and polyaromatic resins which are useful in composite resin structures such as, for example, in aircraft assemblies, and the like. More specifically, the present invention relates to a method of accelerating the cure rate of such resins.
Thermosetting resins which are ethynyl-terminated and which possess a polyaromatic polyimide internal structure are described, for example, in U.S. Pat. Nos. 4,098,767 and 4,100,138. As indicated in those patents, cured resins of this structure are useful in composite materials in aerospace and aircraft structures where high strength, lightweight materials capable of withstanding high temperatures are required. Other work known to those familiar with this art has been performed attempting to optimize the use of ethynyl-terminated aromatic polyimide oligomers.
Analogously, considerable work has been done with aromatic polysulfone resins which are ethynyl-terminated. For example U.S. Pat. Nos. 4,108,926 and 4,131,625 disclose that certain bis-ethynyl aromatic diphenyl-sulfones are effective reactive plasticizers for polysulfone thermoplastic resins, and are themselves useful as high temperature matrix resins.